Speakers buzz until console turns on..? Why?
Moderator: Aaronw
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Speakers buzz until console turns on..? Why?
With the mixer off and the monitors on, there is a major buzz/hum. Not a big deal, I just turn my console on first, but I am still curious. If no signal is sent to the speakers, why would they buzz? I am sure there is a very simple explanation for this. Thanks.
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Hello,
Generally it has to do with "loading" the circuit. Some devices use diodes to power supply to protect and center "ground." For sure the impedance changes when the circuits are powered. There is also the possibility of ground loops and lifted ground with the power off. Maybe your gear has a ground loop that only gets shunted when the common mode rejection (read balanced signal) is functioning. Since I don't know your setup I can not definitly say.
Most Studios have a "turn on" order.
Generally it has to do with "loading" the circuit. Some devices use diodes to power supply to protect and center "ground." For sure the impedance changes when the circuits are powered. There is also the possibility of ground loops and lifted ground with the power off. Maybe your gear has a ground loop that only gets shunted when the common mode rejection (read balanced signal) is functioning. Since I don't know your setup I can not definitly say.
Most Studios have a "turn on" order.
Don T
Music & students - what a gas!
Music & students - what a gas!
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It might be some type of relay circuit on the console outputs used to prevent power-up transients from popping the speakers. The cable ends may just be dangling on the mixer side until it powers up and closes the circuits.
Just a guess.
Thomas
Just a guess.
Thomas
Thomas Barefoot
Barefoot Sound
Barefoot Sound
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